55. Every bus or mini-bus transporting handicapped persons shall comply with the following standards:(1) the wheelchair locking device shall be adequate, not be damaged and be securely fixed to the vehicle;
(2) the platform lift shall be securely fixed to the vehicle, react adequately to the commands of the control mechanism and operate without jerking;
(3) the access ramp shall be securely fixed to the road vehicle at all times and be adequate except if it is deactivated; and
(4) the alarm and locking systems coupled to an access device shall be present and adequate, except if the access ramp is deactivated.